Dithiocarboxylic acids, from

The degradation of tetrachloromethane by a strain of Pseudomonas sp. presents a number of exceptional features. Although was a major product from the metabolism of CCI4, a substantial part of the label was retained in nonvolatile water-soluble residues (Lewis and Crawford 1995). The nature of these was revealed by the isolation of adducts with cysteine and A,A -dimethylethylenediamine, when the intermediates that are formally equivalent to COClj and CSClj were trapped—presumably formed by reaction of the substrate with water and a thiol, respectively. Further examination of this strain classified as Pseudomonas stutzeri strain KC has illuminated novel details of the mechanism. The metabolite pyridine-2,6-dithiocarboxylic acid (Lee et al. 1999) plays a key role in the degradation. Its copper complex produces trichloromethyl and thiyl radicals, and thence the formation of CO2, CS2, and COS (Figure 7.64) (Lewis et al. 2001). 

Berndt et al. [740] have shown that traces of bismuth, cadmium, copper, cobalt, indium, nickel, lead, thallium, and zinc could be separated from samples of seawater, mineral water, and drinking water by complexation with the ammonium salt of pyrrolidine- 1-dithiocarboxylic acid, followed by filtration through a filter covered with a layer of active carbon. Sample volumes could range from 100 ml to 10 litres. The elements were dissolved in nitric acid and then determined by atomic absorption or inductively coupled plasma optical emission spectrometry. 

Of particular interest are some intramolecular cyclizations, which are used for the preparation of dithiazolium salts. There are three different routes all starting from sodium salts of dithiocarboxylic acids (196) (Scheme 33). 

Goewie et al. (19) developed an organometallic-silica bonded phase for the selective retention of phenylurea herbicides and anilines from water. Seven-micrometer diameter silica was derivatized with 2-amino-1-cyclopentene-l-dithiocarboxylic acid (ACDA), resulting in Structure I. Capacity factors of phenylurea herbicides and corresponding anilines were measured on the ACDA-silica and ACDA-metal-loaded silica. The platinum-loaded material was found to selectively retain the anilines. Anilines could be eluted with acetonitrile, but not with methanol or tetrahydrofuran, because of the strength with which acetonitrile forms complexes with platinum and thus displaces the anilines. Application of the ACDA-Pt precolumn in series with an ODS-silica precolumn for... 

Nag et al. have investigated the coordination chemistry of ligands related to or derived from 2-aminocyclopentene-l-dithiocarboxylic acid, concluding N—S bidentate behaviour for the complexes in general.103 With MoVI, however, this ligand and iV-alkyl derivatives are observed to function rather as S—S bidentates.104... 

This method is not general and only a limited number of 5-alkyl-l,2,3,4-thiatriazoles were prepared by this reaction. Ikeda and co-workers have described a convenient method for the synthesis of both 5-alkyl- and 5-aryl-l,2,3,4-thiatriazoles 9 by reaction of l-methyl-2-thioacylpyridinium salts 143 with sodium azide (Scheme 33). Compound 143 can be prepared from pyridium salt 142 by reaction with dithiocarboxylic acid derivatives. The synthesis can conveniently be carried out as a one-pot reaction from 2-chloro-l-pyridinium salt 142 and carbodithioate leading to final compounds 9 in high yields. The 5-alkyl-l,2,3,4-thiatriazoles 9 were isolated as oils <1990S415, 1990ZC67>. 

Compounds containing divalent tellurium, in which the tellurium atom is bonded via one or more heteroatoms to at least one carbon atom, can be formally considered as mixed anhydrides formed from telluroxylic acid and another acid, for instance a dithiocarboxylic acid. 

The addition of amine to the bicyclic salt (96) initially takes place not in position 3, but in position 5, as in the reaction with mercaptans the reaction then proceeds by the same steps to yield the ester of the 1-aminocyclopent-l-ene 2-dithiocarboxylic acid (118). This ester (118) is obtained in yields of 30-65% its structure has been confirmed by independent synthesis from 119. This reaction course is again confined to the special system 118, the homologous tetramethylene-trithionium salts yielding Schiff s bases on reaction with primary amines under the same conditions.50... 

The reaction of CH acidic compounds with CS2 in the presence of excess base yields dianions of dithiocarboxylic acids. Starting from camphor, neutralization with HCl and addition of primary amines yields 3-oxonorbomanethiocarboxamides (11) with undefined stereochemistry (Scheme 3). ... 

Thioacyl chlorides, RCSCl, are powerful thioacylating agents as is obvious from the quantitative thiobenzoylation of the only moderately nucleophilic nitrogen in thiocarbamate (13 equation 5). However, severe limitations are the difficult accessibility of thioacyl chlorides and their thermal lability. Even if they are prepared from dithiocarboxylic acids using an improved procedure, only thioaroyl chlorides, particularly PhCSCl (12), can be handled sufficiently easily to be used in synthetic work. Thus, various azoles react with (12) to furnish /V-thiobenzoyl azolides (14) in the presence of excess azole or NEts (equation 6) a particularly clean and fast reaction is achieved if IV-silylated azoles are employed. However, considering the fact that the chloride has to be prepared from the dithiocarboxylic acid, the approach of equation (4) presents a shortcut to the products. 

Thiols can also be thioacylated, in the same way as alcohols (Section 2.5.3.2), by reaction with bis-thioacyl thioanhydrides (equation 58). The preparation of aromatic as well as aliphatic thioanhydrides is possible according to novel procedures described by Kato et a/., e.g. from the corresponding dithiocarboxylic acids and DCC or 2-chloro-N-methylpyridinium iodide.Even sterically hindered di-thioesters are obtained (equation 58). ... 

Iodotriethyl(nthotrithiobenzoate, a readily accessible compound, on reaction with methanol loses ethanethiol to give the methylorthobenzoate (421 equation 198). Dialkoxydibutylstannanes convert dithiocarboxylic acid esters to oithoesters (422 equation 199). From orthoesters and chloral the orthoesters (423 equation 200) can be synthesized. "... 

Under basic conditions, carbanions derived from thiones, thionoesters, or thioamides react with carbon disulfide to give dithiocarboxylic acids, or derivatives that can be cyclized to 1,2-dithioles <76BCJ3128, 80LA483>, For example, the thioindoxyl (130) forms the dithioloindole (131) <82AHC(3i)63>. The 3-aminocarbanions (132) give bis-l,2-dithiol-3-ylidenes (9), probably via 1,2-dithiole-3-thiones (2a) <82ZOR274>. 

Arenesulfenyl chlorides can be prepared by chlorinating cleavage of aryl benzyl sulfides by means of sulfuryl chloride,651 and thiocarbonyl chlorides similarly from dithiocarboxylic acids and thionyl chloride.652... 

Tolyl dithiocarboxylic acid prepared from />-tolylmagnesium bromide and carbon bisulfide is converted by treatment with semicarbazine into -tolualdehyde semicarbazone, which is hydrolyzed to -tolualdehyde. Wuyts, Berman and Lacourt, Bull. Soc. chim. Belg. 40, 665 (1931) [C. A. 26, 2723 (1932)]. 

Some S-glucuronides are formed from aliphatic thiols, aromatic thiols and dithiocarboxylic acids. As for C-glucuronidation, this reaction is seen in humans for 1,3-dicarbonyl drugs, such as sulfinpyrazone. 

The zinc(II) complex 59 was obtained by the reaction of Zn(MeCN)4(BF4)2 with the corresponding sodium salt of dithiocarboxylic acid and subsequent recrystallization from pyridine (Fig. 15) [114]. The crystal structure was shown to be a distorted trigonal bipyramidal geometry with one sulfur atom from each of the dithiocarboxylato ligands occupying the axial sites. In the absence of donor molecules such as pyridine, one sulfur atom from the dithiocarboxylato ligand coordinates to another zinc center to form a dimer-like Zn(II) complex 60 in the crystalline state [115]. EXAFS study indicates that 60 retains the dimeric nature in the mesophase. 

Scheme 20 Syntheses of ammonium ditbiocarboxylates from the corresponding dithiocarboxylic acids...

Finally, it is to be mentioned that, along with dithiolethione derivative 253, hexathiaadamantane 254 which contains 1,3,5-trithiane ring moieties has been synthesized from dithiocarboxylic acid derivatives by reaction with CuCl2 and Na2S20s in water <1986IZV1206> (Scheme 74). Structure 254 was assigned unequivocally by NMR spectroscopy and MS. 

Sodium hydrogen sulfide Thiocarboxylic acid chlorides from dithiocarboxylic acid esters via dithiocarboxylic acids... 

Monotbio-j -diketones. Acetophenone added slowly with stirring to a suspension of NaNHg in ether, after 15 min. an ethereal soln. of 0-methyl thiobenzoate added, stirred 3 hrs., and allowed to stand overnight monothiodibenzoyl-methane. Y 68%. E. Uhlemann and H. Muller, Ang. Gh. 77, 172 (1965) with Li, also from dithiocarboxylic acid esters, and f. method, s. E. Uhlemann and H. Muller, J. pr. 30, 163 (1965). 

Alkylidene-l,3-dithiacycloalkanes from dithiocarboxylic acid cfaloralkyl esters... 

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